Aqueous process for the quantitative conversion of polyepichlorohydrin to glycidyl azide polymer

Abstract

An aqueous process for the quantitative conversion of polyepichlorodrin (PECH) to glycidyl azide polymer (GAP), using a phase transfer catalyst, is disclosed.

What is claimed and desired to be secured by Letters Patent of the United States is: 
     
       1. An aqueous process for the quantitative conversion of polyepichlorohydrin (PECH) to glycidyl azide polymer (GAP), comprises the steps of: combining said PECH and an ionic azide in a mixture of water and a phase transfer catalyst capable of the quantitative conversion of PECH to GAP;   reacting said PECH and said ionic azide in said aqueous mixture while agitating said mixture at a temperature between about 25° C. and about 100° C., and wherein said aqueous mixture is maintained under a nitrogen purged environment; and   recovering said GAP from said aqueous mixture by separating the aqueous layer from the product layer; water-washing said product layer to remove any inorganic salts remaining in the product layer;   alcohol-washing said water-washed product layer so as to remove said phase transfer catalyst;   dissolving said alcohol-washed product layer in a low-boiling, non-polar solvent;   purifying said dissolved product layer by passing it through adsorbents capable of removing impurities; and   concentrating said purified product layer so as to remove said low-boiling non-polar solvent.     
     
     
       2. The process of claim 1 wherein there is about a 5 to about a 25 percent molar excess of said ionic azide. 
     
     
       3. The process of claim 2 wherein said molar excess range is from about 10 to about 15 percent. 
     
     
       4. The process of claim 1 wherein said ionic azide is selected from the group consisting of sodium azide, lithium azide, and potassium azide. 
     
     
       5. The process of claim 4 wherein said ionic azide is sodium azide. 
     
     
       6. The process of claim 1 wherein said phase transfer catalysts are selected from the group consisting of tertiary amines. 
     
     
       7. The process of claim 1 wherein said phase transfer catalyst is methyl tricapryl ammonium chloride. 
     
     
       8. The process of claim 1 wherein said phase transfer catalyst is selected from the group consisting of quaternary ammonium compounds. 
     
     
       9. The process of claim 1 wherein the excess of said phase transfer catalyst is from about 5 to about 25 weight percent as related to said polyepichlorohydrin. 
     
     
       10. The process of claim 8 wherein the excess of said phase transfer catalyst is from about 10 to about 20 weight percent. 
     
     
       11. The process of claim 1 wherein said temperature is maintained between about 80° C. and about 100° C. 
     
     
       12. The process of claim 11 wherein said temperature range is maintained between about 90° C. and about 95° C. 
     
     
       13. The process of claim 1 wherein said separating is accomplished by decanting. 
     
     
       14. The process of claim 1 wherein said water-washing is hot water-washing. 
     
     
       15. The process of claim 1 wherein said alcohol washing is effected with an alcohol selected from the group consisting of isopropyl alcohol, methyl alcohol, and ethyl alcohol. 
     
     
       16. The process of claim 15 wherein said alcohol is isopropyl alcohol. 
     
     
       17. The process of claim 1 wherein said low-boiling non-polar solvent is selected from the group consisting of chloroform, carbontetrachloride, and methylene chloride. 
     
     
       18. The process of claim 17 wherein said low-boiling non-polar solvent is methylene chloride. 
     
     
       19. The process of claim 1 wherein said adsorbents are selected from the group consisting of silica gel, alumina, and charcoal. 
     
     
       20. The process of claim 1 wherein said adsorbent is silica gel. 
     
     
       21. The process of claim 1 wherein said concentrating is effected by vacuum distillation.